A rare earth element is one of a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides (having atomic numbers from 57 to 71) plus scandium (atomic number 21) and yttrium (atomic number 39). Rare earth elements are valued for their unique magnetic, optical and catalytic properties, and are used in many technologies including wind turbines, electric vehicles, photovoltaic thin films and fluorescent lighting. Although rare earth elements are fairly abundant in the Earth's crust, rare earth elements are typically dispersed and not often found concentrated as rare earth minerals in economically exploitable ore deposits. The traditional method of extracting rare earth elements from ore is the solvent-exchange method, and consists of first crushing the rock into smaller chunks and then grinding it into a fine dust. Unwanted materials (largely iron oxide minerals and carbonate minerals) are removed using various separation methods, leaving behind an ore of rare earth elements and radioactive material, which are then separated by various chemical leaching processes. These methods are costly, energy intensive, and can produce significant quantities of waste products. Accordingly, there is a need for more rapid, flexible, efficient, and environmentally-friendly extraction and separations processes.